(CNN) The six Forest Service rangers suddenly crouched, whispering, on their way up the rocky mountain trail. It was early Friday afternoon, the first day of the Tombstone Shovel Brigade, and the rangers were out in force, hiking to the spot where dozens of volunteers worked with picks and shovels to move and bury Tombstone’s makeshift water line.

Shhh! Look! Do you see it?

The rangers stopped in their tracks. Binoculars emerged from pockets, and fingers pointed to a stand of trees.

And there it was, a Mexican spotted owl, perched high in a pine tree. It was a male, the rangers said, with his back turned to the intruders. He scratched and preened. But mostly, the owl seemed to be watching the nest in a nearby sycamore tree where his mate tended to an owlet.